Table 4.

Odds Ratios for the Association Between Duration of DM and Risk of Colon^a Adenomas in a Matched Case-Control Study^b Nested in the Black Women's Health Study, 1997–2009

DM Status and Duration, Yearsc	All Participants				Age ≤55 Years				Age >55 Years
	No. of Cases	No. of Controls	Multivariable-adjustedd ORe	95% CI	No. of Cases	No. of Controls	Multivariable-adjustedd ORe	95% CI	No. of Cases	No. of Controls	Multivariable-adjustedd ORe	95% CI
No DM	748	2,212	1.00	Referent	401	1,234	1.00	Referent	347	978	1.00	Referent
Yes DM
≤5	51	137	1.07	0.73, 1.56	26	54	1.42	0.80, 2.54	25	83	0.82	0.48, 1.39
5–9	21	71	0.87	0.50, 1.51	12	27	1.35	0.62, 2.92	9	44	0.59	0.26, 1.32
≥10	33	139	0.60	0.39, 0.94	10	32	0.85	0.37, 1.97	23	107	0.52	0.31, 0.89
Ptrend			0.04				0.66				<0.01

Abbreviations: CI, confidence interval; DM, diabetes mellitus; OR, odds ratio.

^a Cases with only rectal adenoma(s) and matched controls were excluded.

^b Cases and controls were matched on age and follow-up time.

^c Duration of DM was calculated on the basis of the year of diagnosis reported by participants. For participants who did not report year of diagnosis but who reported a new diagnosis of DM on the follow-up questionnaire, the date of diagnosis was assumed to be the midpoint of the 2-year follow-up interval.

^d Adjusted for age, educational status, body mass index (weight (kg)/height (m)²), physical activity, family history of colorectal cancer in a first-degree relative, menopausal status, smoking status, alcohol intake, total energy intake, red meat intake, fruit and vegetable intake, and regular aspirin use.

^e Based on a conditional logistic regression model.